Adults with respiratory syncytial virus-associated acute respiratory infection (RSV-ARI) have a nearly threefold higher risk of death within one year compared to the general population. This is according to new research presented at the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Global 2025 in Vienna, Austria.
RSV-ARI includes multiple illnesses caused by RSV, a common and highly contagious virus that can lead to serious complications, such as pneumonia and chronic respiratory disease.
The Danish nationwide cohort study analyzed data from 5,289 adults who were diagnosed with RSV-ARI between 2011 and 2022, comparing them to 15,867 matched controls from the general population. Researchers assessed clinical and economic outcomes up to a year following initial onset.
Adults with RSV-ARI experienced significantly worse health outcomes and a 2.7-times higher risk of death. During the year-long follow-up period, exacerbations of COPD and asthma were 3.1 and 4.6 times more frequent in RSV-ARI patients, respectively. Hospitalization rates for RSV-ARI patients were more than double those of the control group (57% versus 28%), and intensive care unit admissions were almost four times higher (5.3% versus 1.4%).
Beyond the physical considerations of RSV-ARI, the economic impact was considerable. Total direct health care costs for the RSV-ARI patients during the 365-day duration amounted to €20,181 — more than double the €8,085 spent on health care for individuals within the control group.
“One of the most striking findings from this study was the prolonged and significant impact of RSV-ARI,” said lead author and epidemiologist Maria João Fonseca, PhD, in a press release. “Even after the acute phase, patients continued to experience worse outcomes compared to the general population. This underscores just how serious and enduring the effects of RSV-ARI can be.”
Fonseca and colleagues said the data emphasize the under recognized, long-term health and economic repercussions of RSV-ARI in adults, especially those with underlying conditions such as COPD and asthma. Co-author Stanislava Bratković, MD, said she hopes the findings will initiate a push for adults to vaccinate for RSV and promote additional analyses to better understand the global impact.
“Vaccination has proven highly effective in preventing severe outcomes from RSV. … [It] is essential to reduce both health complications and associated costs,” said Dr. Bratković, who is a medical advisor for vaccines at GSK in Denmark. “Looking forward, we hope our findings will inspire further research into the broader clinical and societal burden of RSV, particularly in high-risk groups. This will help shape more targeted preventive strategies and ensure timely interventions for those who need it most.”
